Brush-holder.



A. KIMBLE.

BRUSH HOLDER.

APPLICATION TILED MAR 22.

Patented Dec; 7. 1909.

i y'vx W74 2 W B} UNITED srarns rnirnivr OFFICE.

AUSTIN KIMBLE, OF CHICAGO, ILLINOIS, ASSIGNOR T KIMIBLE ELECTRIC COMPANY,

OF CHICAGO, ILLINOIS.

BRUSH-HGLDER.

Specification of Letters Patent.

Application filed March 22, 1909. Serial No. 484,996.

To all whom it may concern:

Be It known that I, Ansrn: KYMBLE, a

. citizen of the United States of America, and

a resident of Chicago, Cook county, State of Illinois, have invented certain new and useful Improvements in Brush folders, of which the following is a specification.

The main objects of this invention are to provide an improved form of brush holder particularly adapted for the purpose of pre venting destruction of the contact member to provide a device of this class capable of opening the circuit before injury to the com mutator and brush holder is possible; to pro vide an improved mechanism capable oi being controlled by the wear of the contact surfaces and adapted to positively insure the opening of the circuit at a predetermined brush position or at the limit of safe brush operation; to provide improved means for rigidly securing the operating mechanism whereby the mechanism will be positively leased at a predetermined danger point; and to provide improved means whereby the operating mechanism may be readily reset when the worn out brush is replaced by a new one. -A' Specific construction embodying this in -,vention is illustrated in the accompanying drawings, in which:

Figure-1 is a side elevation of a brush holder, being partly broken away to show the method of seating the releasing device in a socket in the brush. The position of the commutator or contact member is rep-re sented by the circle under the brush. Fig. 2 is a detail broad side View of the prepared carbon brush. Fig. 3 is a view corresponding to 'Fig. -1, but showing the brush held clear of the commutator by means of the releasing device, after the brush has been worn down to the releasina point.

In the form shown in the drawings, the brush holder 1 may be of any usual construction, urged by a spring 2 to carry the brush 3 into contact with the contact member. The brush 3 consists of a block of carbon which is secured to the brush holder 1 by means of a screw 4. on the side of the brush holder ad: jacent to the commutator there is secured a spring 5 whichcairies a block 6 of insulating material at its end. The end or" the insu- Jntin block is seated in a cavityin the adjacent ace of the brush 3. In Fig. 2 the screw hole is designated 7, and the recess in which the block this seated is designated 8.

fore the brush has been worn down far enough to bring the metal parts of the brush holder in contact with the commutator. Assume, for example, a form of motor which does not require immediate attention and may be remotely controlled by the operator; it will frequently happen that the oommiv tator and brush holders are ruined, through the fact that the brush is worn out and allows the br sh holder to engage the commutator. The friction and sparking between the parts will rapidly destroy the commutator and brush holder without giving any warning of the injury which is taking place. With an automatic release, the electric circuit will be opened at a predetermined limit, of safe brush operation, and the motor will be brought to a full stop before the metal parts of the commutator and brush holder are allowed to come into contact.

Although but one specific embodiment of this invention is herein shown, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit or scope of this invention.

I claim:

1. In a dynamo electric machine, the combination of a movable contact member, a

brush bearing on said contact member, a spring arranged to throw said brush away from said contact member, and means for,

automatically releasing said spring when the brush has been wornto a certain point.

2. In a dynamo electric machine, the combination of a movable contact member, a

brush bearing on said contact member, a

spring adapted to act between the brush and contact member, means for holding said spring in a retracted position, and means for automatically releasing said spring to throw said brush away from said contact member when said brush has been worn to a certain point.

In a dynamo electric machine, the combination of a movable contact member, a brush bearing on said contact member, a spring adapted to act between the brush r;

Patented Dec. 7, 1909.

contact member, means for holding said spring in a retracted position, and means for autoimitically releasing said spring to throw said brush away from said contact member when said brush has been Worn to a certain point, and a block of insulation carried by said spring and adapted to engage the contact member and insulate the brush after the release oi said sp ng.

member and insulate the brush after the m lease of said spring, and insulating material interposed between the brush holder and contact member in such the short-circuiting thereof by said s ring. 25

manner as to prevent 5. In a d namo electric machine, t a combination o a movable contact member, a brush bearing on said contact member," a spring adapted to act between the brush and contact member, there being a socket in the 30 brush for holding said spring in a retracted osition, easing said spring when said brush has been worn to a certain point.

and means for automatically re-.

Signed at Chicago this 10th day of March 35 AUSTIN KIMBLE.

lVitnesses:

EDWIN PilELPS, MARY M. DILLMAN. 

